生态农业经营模式浅析     

庄硕 《黑龙江农业科学》2014,(4):126-128

生态农业经营是建立在生态环境发展基础上的经济性复合农业系统,不同地区的经营模式是由地域特色所决定的,生态农业经营模式具有多样性、效率性、综合性以及持续性等优势,在经营模式中能够将经济与生态的有效循环体现出来。为实现生态农业经营的发展与经济效益的最大化,现就生态农场的经营模式进行分析,并找出主导现代农业发展的因素与生态农业发展经营的方向。  相似文献   

施氏鲟幼鱼摄食和生长的最适水温   总被引：15，自引：3，他引：15  

李大鹏  庄平  严安生  章龙珍 《中国水产科学》2005,12(3):294-299

实验用施氏鲟(AcipenserschrenckiiBrandt)幼鱼为黑龙江捕获的野生亲本经人工繁殖、培育所得,8月龄,体长(32 63±1 80)cm,实验周期35d。实验设计了4个水温处理组,实验水温分别为17℃、20℃、23℃和26℃,实验观察到,生活在不同水温环境中的幼鱼表现出不同的生长特性,养殖在23℃温度环境中的施氏鲟幼鱼的生长速度显著高于其他处理组幼鱼,水温对施氏鲟的特定生长率(SGR)、日增重(DWG)、食物转化率(FCR)和摄食率(FR)有着显著的影响。这些参数与水温(T)之间的相关关系可用二次回归曲线来描述,生长率与水温的回归方程式为:SGR=-12 933+1 418T+(-0 033)T2,摄食率与水温的关系式为:FR=-5 324+0 719T+(-0 016)T2。根据回归方程,求得施氏鲟幼鱼的最适生长水温为21 53℃,最大摄食率的水温为22 33℃。结论认为,施氏鲟在水温17～26℃都可摄食生长,但在20℃时最适宜;同时证实,施氏鲟最适生长温度要低于其最适摄食温度。  相似文献   

水产养殖中使用氰化钠毒杀敌害生物对海洋生态环境影响的探讨     

庄宏儒 《福建水产》2006,(2):33-37

在水产养殖中,氰化物被用于毒杀敌害生物,但有关使用氰化物对海洋生态环境影响鲜有报道。本文从氰化钠在海洋环境中的迁移转化,对生物体的毒性效应,对生态系统的影响等方面进行探讨,研究表明:在水产养殖中合理使用氰化钠,对生态环境和人类健康不会造成有害的影响。  相似文献   

山东近海石鲽的同工酶分析   总被引：4，自引：2，他引：4  

刘曼红  高天翔  于常红  陈四清  庄志猛 《海洋水产研究》2005,26(1):41-48

采用水平淀粉凝胶电泳技术研究山东半岛南岸海阳近海石鲽同工酶的组织特异性及群体遗传结构。结果表明，石鲽的眼、鳃、肌肉、心脏、肝脏、肾脏、脾脏和鳍条共8种组织的17种同工酶表达有明显的组织特异性。对肝脏和肌肉两种组织的AAT、ADH、EST、GPI、G3PDH、IDHP、LAP、LDH、MDH、MPI、PGDH、PGM、SDH和SOD等14种同工酶进行了遗传学分析，共记录了21个基因座位，其中，GPI-2^*、JDHP-2^*、MDH-1^*、MPI-1^*、PGM-3^*、SDH^*共6个基因座位呈多态，其多态座位比例为0．2857(P0.99)，平均观测杂合度和预期杂合度分别为0．0321和0．0283，平均有效等位基因数为1．3650，遗传偏离指数均大于零。石鲽和圆斑星鲽同工酶比较分析表明，二者在AAT^*、ADH^*、GPI-1^*、IDHP^*、LDH^*、MDH-1^*、MDH-2^*、MDH-3^*、MPI-1^*、PGM-1^*、PGM-2^*、SOD^*和SDH^*存在基因置换或近于基因置换，两种间的遗传距离为1．3117。  相似文献   

人工养殖西伯利亚鲟精子超低温冷冻保存研究   总被引：7，自引：6，他引：7  

刘鹏  庄平  章龙珍  王斌  闫文罡 《海洋渔业》2007,29(2):120-127

研究了人工养殖西伯利亚鲟精子的生物学特征及超低温冷冻保存方法。西伯利亚鲟的产精量为113.67±39.86 ml,精子密度为(6.49±3.10)×108/ml,精子活力为(85.4±9.5)%,精子寿命为353±23 s。精子密度与精子快速运动时间、精子寿命之间均存在线性相关,用方程分别表示为:y=1.0384x+1.5089(R2=0.7325);y=2.9069x+74.289(R2=0.6967)。结果表明精子密度可作为一项精子质量评价的标准。通过比较西伯利亚鲟精子在不同稀释液、不同抗冻剂和抗冻剂浓度、降温速率、解冻温度下的保存效果,结果表明:配方2作为稀释液,18%甲醇作为抗冻剂,二步法超低温(-196℃)冷冻保存精子,40℃水浴解冻取得最好的冻后活力,解冻后活力为(51.8±5.8)%。西伯利亚鲟授精的最佳精卵比为106∶1。在此精卵比下用冻精授精分别得到了(72.3±3)%的受精率和(52.9±4.1)%的孵化率,其中受精率与鲜精没有显著性差异,孵化率与鲜精有显著差异(P<0.05)。  相似文献   

兔肺炎双球菌病的病原分离鉴定及治疗     

莫玲  王文秀  刘吉山  姚春阳  庄金秋  王艳  韩文瑜  沈志强 《动物医学进展》2014,(11)

2013年山东滨州市某兔场发生仔兔高病死率、母兔流产的疾病。为了诊断治疗该病,本试验采集病死兔肺脏进行病原的分离,通过病原分离、形态学观察、生理生化试验、溶血试验、药敏试验等试验,证实分离菌为肺炎双球菌。该菌具有α-溶血性,对青霉素、头孢吡肟、阿米卡星等药物敏感;动物回归试验成功复制出兔肺炎双球菌病,症状典型,病理剖检变化明显。根据临床症状和药敏试验结果,用青霉素等药物进行治疗,病情得到有效控制。  相似文献   

不同固含量低分子酚醛树脂浸渍改性杉木板材性能的研究   总被引：4，自引：0，他引：4  

王向歌  金菊婉  邓玉和  韩书广  庄寿增 《西南林业大学学报》2014,(3):84-88

为改善杉木的物理力学性能,采用真空-加压浸渍工艺,对速生杉木进行低分子酚醛树脂增强改性处理,分析不同树脂增重率对改性杉木性能的影响,以及树脂在木材长度和厚度方向上的分布特点。结果表明,杉木经过固含量为10％、20％、30％的酚醛树脂浸渍处理后,其尺寸稳定性随树脂固含量的增加逐渐提高,静曲强度由64.5 MPa提高至75.0 MPa,弹性模量和表面硬度分别提高了6.1％、27.5％、48.2％和29.8％、63.1％、73.8％,但冲击韧性随着树脂增重率的增加而逐渐降低;树脂在木材长度方向上分布均匀,在厚度方向上木材表面多于其内部。  相似文献   

Vaspin and insulin signaling pathways in obstructive sleep apnea-hypopnea syndrome animal model     

ZHUANG Xiang-hua  NI Yi-hong  LIU Yuan-tao  SUN Ai-li  SUN Fu-dun  JIANG Dong-qing  LI Xiao-bo  CHEN Shi-hong 《园艺学报》2014,30(11):2084-2088

AIM: To establish a suitable chronic intermittent hypoxia (CIH) model in rats for modeling the obstructive sleep apnea-hypopnea syndrome (OSAHS) and further to explore the relationship between vaspin and insulin signaling pathways at mRNA and protein levels. METHODS: Healthy male Wistar rats were divided into control group and CIH group. The rats in control group were raised under physiological condition, and the rats in CIH group were kept in the plexiglass chamber between 9:00~17:00 and underwent intermittent hypoxic challenge 8 h/d for 8 weeks. The blood pressure of arteria caudilis in the rats was measured by tail cannulation before and after study. Fasting plasma glucose (FPG), total cholesterol (TC), triglycerides (TG), fasting insulin (FINS), vaspin and adiponectin levels were measured. The mRNA expression of vaspin was detected by real-time PCR. The protein levels of vaspin, Akt and p-Akt were determined by Western blotting.RESULTS: Before the experiment, the weight and blood pressure of the rats had no significant difference, while after the experiment the blood pressure in CIH group was obviously higher than that in control group. FPG, FINS, TG and TC in CIH group were also markedly higher than those in control group (P<0.05). Serum vaspin concentration was significantly correlated with FPG, FINS, HOMA-IR and TC. The expression of vaspin at mRNA and protein levels in the fat tissue of CIH group was evidently higher than that in control group. The protein levels of p-Akt decreased distinctly in CIH group. CONCLUSION: The levels of FINS, HOMA-IR, SaO2 and vaspin were markedly higher than those in control group, indicating that there was a close relationship between vaspin and insulin resistance in OSAHS.  相似文献   

Transwell contact co-culture promotes growth and differentiation of single-dissociated iPSCs     

LIU Qing  GUO Yong-long  GUO Xiao-ling  LIAN Rui-ling  CHEN Jian-su 《园艺学报》2014,30(8):1404-1409

AIM：To investigate the promoting role of Transwell contact co-culture system in the growth and differentiation of single-dissociated induced pluripotent stem cells (iPSCs). METHODS：Bovine corneal endothelial cells (CECs) at passage 1~2 (P1~2) were seeded on the underside of Transwell inserts placed into culture plates and were cultured in 37 ℃ and 5% CO2 for 8 h. Accutase digestion and 40 μm filter process disaggregated colony-aggregated iPSCs into single-dissociated iPSCs, and the cells were seeded on the inside of Transwell inserts with CECs in medium of mTeSR1 for 3 d and then in low-glucose DMEM supplemented with 10% FBS for 2 weeks. The characteristics and differentiation markers were evaluated by real-time fluorescence quantitative polymerase chain reaction (qPCR), immunofluorescence staining, live & dead cell staining and alkaline phosphatase (ALP) staining. The group of iPSCs cultured in conventional medium was used as control group 1. The group of single-dissociated iPSCs co-cultured with CECs was set as experimental group, while single-dissociated iPSCs without co-culture were as control group 2. RESULTS：The bovine CECs showed typical hexagonal cobblestone shape. iPSCs showed colony-like growth, while became single-dissociated cells after Transwell contact co-culture with bovine CECs for 3 d. The single-dissociated iPSCs positively expressed the undifferentiated markers, Nanog and Oct4. The mRNA expression levels of Nanog, Oct4 and Sox2 between experimental group and control group 1 were both positive and had no statistical significance difference (P>0.05). The dead cells in experimental group decreased significantly, and there was statistically significant difference compared to control group 2 (P<0.01). After 14 d of induced differentiation co-culture, the single-dissociated iPSCs showed rather uniform polygonal morphology, increased dimension and no obvious colony existence. Negative ALP staining, positive immunofluorescence staining for ZO-1, AQP1 and CD31, and negative for CD34 and CD133 were also observed. The results of qPCR showed that the mRNA expression of Oct4, Nanog and Sox2 significantly decreased, and had statistically significant difference compared with control group 1 (P<0.01). CONCLUSION：When co-cultured with bovine CECs, iPSCs morphologically changed to endothelial-like cells and expressed some markers of CECs. Transwell contact co-culture system not only enhances the growth of single-dissociated iPSCs, but also promotes their differentiation.  相似文献   

野生及人工养殖半滑舌鳎肌肉营养成分分析研究   总被引：11，自引：0，他引：11  

马爱军  刘新富  翟毓秀  柳学周  庄志猛 《海洋水产研究》2006,27(2):49-54

分析了野生及人工养殖条件下半滑舌鳎背部肌肉的一般营养成分、氨基酸、脂肪酸及常量和微量元素的组成。结果表明,野生与养殖半滑舌鳎的蛋白质含量差异较小,分别为17.20%和17.17%;野生与养殖半滑舌鳎的脂肪含量相对较低,分别为0.15%和2.41%。两者均富含常量和微量元素,其中野生半滑舌鳎的硒和锌含量分别为7.92%和6.29%,较养殖半滑舌鳎高。在氨基酸含量方面,养殖半滑舌鳎呈味氨基酸天冬氨酸、谷氨酸、甘氨酸和丙氨酸略低于野生半滑舌鳎。不饱和脂肪酸的总含量两者相似。但养殖半滑舌鳎C19∶1含量为20.41%,明显高于野生半滑舌鳎的含量(11.68%)。野生半滑舌鳎在C22∶6(DHA)的含量为14.28%,高于养殖半滑舌鳎的含量(10.39%)。  相似文献